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I'm a well-known mainframe performance guy, with almost 30 years of experience helping customers manage systems. I also dabble in lots of other technology. I've sought to widen the Performance role, incorporating aspects of infrastructural architecture.
I'm a world-famous podcaster and screencaster (albeit VERY thinly spread). :-)

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I hope you don't get the idea I'm overly into rigour, talking about Classification. But I think it has to be done - to provide terminology for this series of posts. This is the second of four posts on Batch Parallelism, following on from
Motivation . If I think about how parallelism works in batch it broadly falls into two camps: Heterogeneous Homogeneous ( If you look these two terms up in... [More]

It may surprise you to know I hate asking questions to which I already know the answers. And I hate even more "leaving understanding on the table". Let me put it more positively: I love it when I can glean new insights into existing data. This post is about precisely that: An experiment in gleaning extra understanding... In Batch Architecture, Part Zero and follow-on posts I talked... [More]

First a word of thanks to Ferdy for his insightful comment on Batch Architecture, Part Zero . And also to my IBM colleague Torsten Michelmann for his offline note on the subject. As I indicated in Part Zero I hoped to talk about jobs in a subsequent post. And this is that post. In particular I want to discuss Viewing jobs as part of distinct applications, and Generating a high-level understanding... [More]

I've written extensively in the past about what you can glean about batch suites from SMF, most notably SMF Type 30. While I don't believe SMF alone can give you the full dependency network (complete with validation) I've just added some analysis to my code that gets me a little closer. As you're probably never going to run my code the bit that would be interesting is the kind of inferences it's... [More]

As mentioned here , I recently participated in a residency in Poughkeepsie. Our task was to write the "Batch Optimization on z/OS" redbook that we hope will get out soon (though I think early next year is the most realistic timescale). These past two weeks I "toured" the redbook in the Nordics: 5 cities in 2 weeks (Helsinki, Copenhagen, Oslo, Stockholm and Aarhus). I really... [More]

Up until now I haven't talked much about DB2, except perhaps to
note it's a little different. But what is a DB2 Batch job anyway? It's
important to note a DB2 job ISN'T necessarily exclusively DB2 - although
some are. It's just a job that has some DB2 in it. The reason for writing a separate post, apart from breaking things
up a little, is because batch jobs with DB2 in them present... [More]

I concluded Batch Architecture - Part One with a brief mention of inter-relationships and data. I'd like to expand on that on this part. Often the inter-relationships between applications are data driven - which is why I'm linking the two in this post (and in my thinking). But let's think about the inter-relationships that matter. There are four levels: Between applications. Between jobs. Between... [More]

In WLM Velocity - "Rhetorical Devices Are Us" I mentioned a graph I wasn't going to publish - essentially to protect a customer. In this post I'm again going to describe a graph I have (at least in my head) without publishing it. (And for essentially the same reasons.) I hope you find it useful, however:
I've been acquainted with a lot of customer Batch Window Reduction projects,... [More]

In October Frank Kyne and I expect to run a residency in Poughkeepsie.
You can find the announcement here . The residency builds on the ideas presented here and three subsequent posts. I revisited a specific part of it in
Cloning Fan-In . So what are we going to do? For a start we're going to assemble a team of 4 skilled mainframe folks from wherever we can. One of them will be me, which leaves... [More]

Usually when I go away on holiday I bring something back with me. Often in the form of fresh ideas. This year it's been such a hectic one that all I did was to flake out. So no new ideas this time. Perhaps that's a good thing, perhaps not. But I think I did achieve something: Mental decluttering. So I can, for example, look at stuff I was working on with a fresh take. And the timing is... [More]